I just ran across a little report on the history of SooperLooper by EnKerli in another forum:
“While MOD is mentioned as the developer of SooperLooper in the plugin itself, it’s a version MOD has ported , forked from the brunogola plugin version , which is itself based on the old Jesse Chappell LADSPA plugin of the standalone SooperLooper by the very same Jesse Chappell, aka Sonosaurus .”
The Face of Standalone SooperLooper
Amendment:
One looper experimenter said the Sooperlooper is based on the Gibson EDP-4 (Echoplex Digital Pro Plus) rev 4 software was used in 2001-2007 versions.
(It had an optional 7 button, near 19" wide foot controller)
A 11:20 review of the Echoplex features and history.